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SEMI P39-0304 E2 © SEMI 2004 6 7.4.2 The set of printable ASCII characters consists of hexadecimal ch aracter codes 21-7E. In ascending order of character code, we ha ve: !"#$%&’()*+,-./0123456789:;<=>?@ […

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Table 3 Real Number Types

Format Meaning

‘0’ unsigned-integer Positive whole number

‘1’ unsigned-integer Negative whole number

‘2’ unsigned-integer Positive reciprocal

‘3’ unsigned-integer Negative reciprocal

‘4’ unsigned-integer unsigned-integer Positive ratio

‘5’ unsigned-integer unsigned-integer Negative ratio

‘6’ IEEE-4-byte-float Single-precision floating point

‘7’ IEEE-8-byte-float Double-precision floating point

7.3.2 In types 0 and 1, the real is a whole number—its fractional portion is zero. In types 2 and 3, the unsigned-

integer represents the denominator of a reciprocal, with an implicit numerator of 1. Types 4 and 5 are ratios, with the

numerator listed first, followed by the denominator. Types 6 and 7 are binary floating point numbers in IEEE 754-

1985 format, with the least significant byte of the fraction (byte 0) stored first

Figure 3

IEEE Floating Point Formats

Table 4 Real Number Examples

Value Rational Form IEEE-4 Form

0.0 00000000 00000000 00000110 00000000 00000000 00000000 00000000

1.0 00000000 00000001 00000110 00000000 00000000 10000000 00111111

0.5 00000011 00000010 00000110 00000000 00000000 00000000 10111111

0.3125 00000100 00000101 00010000 00000110 00000000 00000000 10100000 00111110

1/3 00000010 00000011 00000110 10101011 10101010 10101010 00111110

2/13 00000101 00000010 00001101 00000110 11011001 10001001 00011101 10111110

7.3.3 EXCEPTION HANDLING

— For types 2–5, a denominator of 0 should be treated as a fatal error. A type

outside the range of 0–7 should be treated as a fatal error.

7.4 Strings

7.4.1 A string is a sequence of zero or more bytes (“characters”) preceded by an unsigned-integer representing the

number of characters in the string:

string -> length byte*

Strings in OASIS are further sub-typed by semantic. A b-string (“binary string”) is a string which may contain any

combination of 8-bit character codes in any sequence. An a-string (“ASCII string”) may contain only printable

ASCII character codes (hexadecimal 21-7E) plus the SP (space) character (hexadecimal 20), in any sequence. An

n-string (“name string”) may contain only printable ASCII character codes (hexadecimal 21-7E), and must have a

length greater than zero.

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7.4.2 The set of printable ASCII characters consists of hexadecimal character codes 21-7E. In ascending order of

character code, we have:

!"#$%&’()*+,-./0123456789:;<=>?@ [21-40]

ABCDEFGHIJKLMNOPQRSTUVWXYZ[\]^_‘ [41-60]

abcdefghijklmnopqrstuvwxyz{|}~ [61-7E]

This excludes space (SP), tabs (HT, VT), and all other control characters.

7.4.3 EXCEPTION HANDLING

— OASIS processors should treat illegal characters in a-strings or n-strings as

fatal errors. Zero-length n-strings should also be treated as fatal errors.

7.5 Deltas

7.5.1 A delta represents geometric data (coordinates, vectors, planar offsets, etc.).

7.5.2 A 1-delta is stored as a signed-integer and represents a horizontal or vertical displacement. Bit 0 encodes

direction: 0 for east or north, 1 for west or south. The remaining bits are the magnitude. Horizontal or vertical

alignment is implied by context.

7.5.3 A 2-delta is stored as an unsigned-integer and represents a horizontal or vertical displacement. Bits 0-1

encode direction: 0 for east, 1 for north, 2 for west, and 3 for south. The remaining bits are the magnitude.

7.5.4 A 3-delta is stored as an unsigned-integer and represents a horizontal, vertical, or 45-degree diagonal

displacement. Bits 0-2 encode direction: 0 for east, 1 for north, 2 for west, 3 for south, 4 for northeast, 5 for

northwest, 6 for southwest, and 7 for southeast. The remaining bits are the magnitude (for horizontal and vertical

deltas) or the magnitude of the projection onto the x- or y-axis (for 45-degree deltas).

7.5.5 A g-delta has two alternative forms and is stored either as a single unsigned-integer or as a pair of unsigned-

integers. The first form is indicated when bit 0 is zero, and represents a horizontal, vertical, or 45-degree diagonal

displacement, with bits 1-3 encoding direction, and the remaining bits storing the magnitude, in the same fashion as

a 3-delta. The second form represents a general (x,y) displacement and is a pair of unsigned-integers. Bit 0 of the

first integer is 1. Bit 1 of the first integer is the x-direction (0 for east, 1 for west). The remaining bits of the first

integer represent the magnitude in the x-direction. Bit 0 of the second integer is the y-direction (0 for north, 1 for

south). The remaining bits of the second integer represent the magnitude in the y-direction. Both forms may appear

in a list of g-deltas.

Figure 4

Delta Types

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Table 5 Delta Examples

Bit Pattern Type Meaning

11111001 00100011 1-delta

 = -2300

11111000 00100011 1-delta

 = +2300

10011000 00101010 2-delta

x = +1350

10011011 00101010 2-delta

y = -1350

11001101 00000001 3-delta

x = -25, y = +25

11010111 00000111 3-delta

x = +122, y = -122

11101001 00000011 01111010 g-delta

x = +122, y = +61

11101100 00000101 g-delta

x = -46, y = -46

10111011 00000001 10110111 00001111 g-delta

x = -46, y = -987

7.6 Repetitions

7.6.1 A repetition represents an “array” of cell placements, geometries, or text elements. The repetition is part of

the PLACEMENT, <geometry>, or TEXT record itself. A repetition consists of an unsigned-integer which

encodes the type, followed by any related repetition parameters:

Table 6 Repetition Types

TYPE

Format

re-use the previous repetition definition

1 x-dimension y-dimension x-space y-space

2 x-dimension x-space

3 y-dimension y-space

x-dimension x-space

... x-space

N-1

x-dimension grid x-space

... x-space

N-1

y-dimension y-space

... y-space

M-1

y-dimension grid y-space

... y-space

M-1

8 n-dimension m-dimension n-displacement m-displacement

9 dimension displacement

dimension displacement

... displacement

P-1

dimension grid displacement

... displacement

P-1

7.6.1.1 x-dimension, y-dimension, x-space, y-space, dimension, n-dimension, m-dimension, and grid are all

unsigned-integers. displacement, n-displacement, and m-displacement are g-deltas.

7.6.2 TYPE 0 indicates that the previous repetition description, stored in modal variable repetition, is to be re-used.

(See Section 10 on page 11.) No additional values are stored with this type.

7.6.3 TYPE 1 is an N-column (N > 1) by M-row (M > 1) matrix with uniform horizontal and vertical spacing

between the elements. x-dimension is N - 2 and y-dimension is M - 2. The (x-offset, y-offset) (cumulative spacing

in the (horizontal,vertical) direction) of element (i,j) of the repetition (i = 0, ..., N-1 and j = 0, ..., M-1) is

(i * x-space, j * y-space).

7.6.4 TYPE 2 is an N-column (N > 1) by 1-row vector with uniform horizontal spacing between the elements. x-

dimension is N - 2. The (x-offset, y-offset) (cumulative spacing in the (horizontal,vertical) direction) of element i of

the repetition (i = 0, ..., N-1) is (i * x-space, 0).

7.6.5 TYPE 3 is a 1-column by M-row (M > 1) vector with uniform vertical spacing between the elements. y-

dimension is M - 2. The (x-offset, y-offset) (cumulative spacing in the (horizontal,vertical) direction) of element j of

the repetition (j = 0, ..., M-1) is (0, j * y-space).